Tana lives in a world where walled cities called Coldtowns exist. In them, quarantined monsters and humans mingle in a decadently bloody mix of predator and prey. The only problem is, once you pass through Coldtown's gates, you can never leave. One morning, after a perfectly ordinary party, Tana wakes up surrounded by corpses. The only other survivors of this massacre are her exasperatingly end...